break down vs misfire

break down is not a noun while misfire is a noun.

Word	Noun	Adjective	Verb	Adverb
break down	No	No	Yes	No
misfire	Yes	No	Yes	No

As verbs, misfire is a hyponym of break down; that is, misfire is a word with a more specific, narrower meaning than break down:

Other hyponyms of break down include crash, go down, blow, blow out, burn out, malfunction, misfunction.

break down (noun)	misfire (noun)
	an explosion that fails to occur
	a failure to hit (or meet or find etc)

break down (verb)	misfire (verb)
collapse due to fatigue, an illness, or a sudden attack	fail to fire or detonate
stop operating or functioning
separate (substances) into constituent elements or parts
make a mathematical, chemical, or grammatical analysis of; break down into components or essential features
make ineffective
cause to fall or collapse
lose control of one's emotions
fall apart